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Airbus have issued an inspection notice saying it's a materials issue, and that airlines should inspect at an aircrafts 4 year inspection interval. They would not do so, and would be overruled by the European safety body EASA, if they thought otherwise.

This has been discussed to death on aviation industry forums, and the general consensus is it's a non-issue - the calls for grounding are being headed by an industry union, not a regulatory body.

Every aircraft has cracks in it, even brand new ones - in this case, it's in a non-critical location and is non-load bearing. A check at the 4 year point is adequate for this type of discovery.

At 00:25 - 00:26, for some strange reason, the news lady says "It's an Airbus jet" very quickly. I don't think the word "Boeing" is even mentioned in the video, yet it is regarding a Boeing 737. Simple slip up? Seems very odd to me.

I was really confused too. I think what's happening is that ABC is actually playing the video for a completely different story -- one about a United Airbus jet going down because the cockpit instrumentation failed -- on top of its text story about the Southwest cracks.

No, its a continuation of union action against Qantas that precipitated the airline voluntarily grounding its entire fleet in October in order to force arbitration in the disputes. The maintenance engineering union is ceasing on any little thing it can to show that maintenance by "other" parties is deficient. They use the same scare tactic equally against Boeing, Airbus and Bombardier (the Q fleet), its just the last few high profile incidents have been Airbus. They rely on ignorance, some of which is on display in this comment stream and Australian media, about what constitutes a threat to safety or a maintenance issue.

Cracks in aircraft (Boeing, Airbus, Embraer or Tiger Moth) are inevitable and routine, as is the inspection for them. In this case there is repair activity that can take place when the aircraft is next in for major work. You could opt to do it earlier at the expense of unscheduled downtime for a "warm fuzzy" feeling, but bean counters are rarely warm and fuzzy.

Aluminum does not have a fatigue limit [wikipedia.org]. That is, there is no way to design an aluminum structure so that it does not experience fatigue (growth of microscopic cracks). Any aluminum structure will eventually fail under cyclic loading like a fuselage experiences (pressurization / depressurization which each flight). That is why pressurized airframes must be retired after about 100,000-120,000 cycles (at which point they are chopped up to prevent an unscrupulous person selling it to an unsuspecting buyer).

Since you cannot prevent the growth of cracks, the best you can do is predict when they will become a problem, and do regular maintenance checks to catch any which may have formed before. In the Southwest incident, it turned out the predicted time til a maintenance check was needed was too long. The crack formed and enlarged to failure sooner than expected. "Admitting" that you know of this "weakness" is simply acknowledging what every materials science student already knows - there is no way to prevent fatigue failure of aluminum. Doesn't matter if it's a Boeing plane or an Airbus plane - every aluminum plane has this weakness.

"Admitting" that you know of this "weakness" is simply acknowledging what every materials science student already knows - there is no way to prevent fatigue failure of aluminum. Doesn't matter if it's a Boeing plane or an Airbus plane - every aluminum plane has this weakness.

Your post comes across as if there is something inherently wrong with using aluminum. Just because aluminum doesn't have a fatigue limit doesn't imply there is a design problem. The fatigue properties are just one of many design aspects that have to be balanced, and there are number of ways to mitigate fatigue risks. Also, the fatigue curve on wiki is generic and not not necessarily representative of a aircraft grade Aluminum Alloy such as 7075. Many high performance aluminum alloys have a sharp knee b

Don't take it for granted that the EASA will do the right thing. The FCC didn't in response to the Windsor incident [wikipedia.org], thus failing to prevent the, at the time, worst ever airliner crash. [wikipedia.org]

Having said that, I'm not going to get worried about this until I see a number of independent aviation engineers getting worried. Your comment on the consensus of aviation industry forums is reassuring.

It's not a composite material, it's a grade of aluminium used in a non-load bearing rib in the wing, used to maintain the wings aerodynamic shape. The cracks were found on one of the feet on the rib, which attach the rib to the wing skin. There are multiple other routes for the load, which is why this is considered non-load bearing and not an issue.

and now, not any country in eu or eu commissions (that are MUCH more stringent than any kind of regulatory body in usa or any place else) have not found any problems with boeings, but, very Inconspicuously, australians did. the fact that boeing's largest outfit outside u.s. is residing in australia, is just a coincidence, i assure you.........

I'd wager this has a whole lot more to do with last year's grounding of the entire fleet (due to negotiations failing with unions) and the ongoing labour dispute than anything technical. As others have already mentioned, the A380 has been widely discussed in aviation-specific forums, it's likely this is a move to highlight the ongoing issues within Qantas

"We confirm that minor cracks were found on some noncritical wing rib-skin attachments on a limited number of A380 aircraft. We have traced the origin. Airbus has developed an inspection and repair procedure, which will be done during regular, routine scheduled four-year maintenance checks. In the meantime, Airbus emphasizes that the safe operation of the A380 fleet is not affected."

1) minor and noncritical2) on a limited number3) traced the origin4) have already found the solution5) have already put it in the inspection list

For some reason, when following your link to the 737 roof ripping problem I'm first shown a video of a smoke issue on an Airbus plane, and only after that does the actual 737 video related to the article show up.

"If the most capable and relevant people we have look at the findings".... Exactly, the initial call to ground the fleet was by the service engineers and the association that represents them. This is not a trivial matter raised by a baggage thrower.

The people who lie are usually the ones with the most to gain/lose. What do service engineers have to gain by grounding the fleet - not much. What would Airbus lose by having their brand new fleet grounded - a huge amount of public confidence.

A radiation therapy machine called Therac-25 had severe design flaws that caused it to kill several people. The AECL engineers and managers were overconfident and over-greedy, respectively, so even after a significant number of accidents they refused to admit that the machine was faulty.

Chances are the problem is quite serious, but Airbus' actuaries tell them that the short-run cost of performing immediate repairs is greater than the long-run cost of their insurance rates after a mechanical failure.

The people who lie are usually the ones with the most to gain/lose. What do service engineers have to gain by grounding the fleet - not much. What would Airbus lose by having their brand new fleet grounded - a huge amount of public confidence.

What do service engineers have to gain?

Well, let's have a bit of context. These aren't just "service engineers", it's the Australian Licensed Aircraft Engineers Association, the trade union for aircraft engineers in Australia.

The same trade union which wants an A380 maintenance hangar in Australia, written into the workplace agreement they were negotiating with Qantas.

They've recently settled that agreement, without getting the hangar, (one source [smh.com.au]), so one presumes they're just keeping their name in the news.

What do service engineers have to gain by grounding the fleet - not much.

Australian service engineers were on strike recently [perthnow.com.au] about keeping QANTAS planes serviced in Australia to preserve Australian service engineer jobs. It's the Australian Licensed Aircraft Engineers Association [smh.com.au] that is calling for the planes to be checked now rather than when they are next due for heavy maintenance as Airbus suggests. I wonder if "checking now" (followed probably by "checking much more often") might make work for some Australian licenced aircraft engineers? While I am inclined to agree with them, I do have to recognise that yes they have something to gain.

Ford says so. Not that the Pinto was really that unsafe, but the lies Ford pushed to cover up their knowledge of problems (or Chrysler and lies about the minivan latches, it's not just Ford, it's all industry in the US, whatever's left). They knew the fix, and they chose to let people burn because it was cheaper. The government sided with them, though a jury didn't.

How dare you use facts!Don't you know American companies are crooked, evil, liars?Wasn't there a 60 minutes spot showing how Pintos wer setting orphanages on fire just by parking nearby?You sir will have to answer to Dan Rather for your sins.AC indeed.

Like it or not, there is, and must be, a price on human life. "But it could kill people!" isn't sufficient reason in itself to ground the A380 - the risks and costs must be balanced.

Pulling some numbers out of the air, for argument's sake this problem has a 10% chance of one day causing a crash, which will kill 400 people, and killing the A380 will cost $20 billion. That is $20 billion to save, on average, 40 lives, or $500 million per life. You could instead tax Airbus more heavily for $500 million, and put the money into a branch of health care which on average saves one person per $500,000. The economy is $19.5 billion better off and the population is 960 people better off, by letting the 380 keep flying despite the fact that "it might kill people".

You even place a value on your own life. Do you own and habitually wear a bullet proof vest? Do you wear a crash helmet when driving? Do you buy a new vehicle every year with safety features almost entirely dictating your choice? If not, it is because you value money (and other benefits such as comfort and avoiding ridicule) over slight reductions in your chance of an early death.

(Note: I don't know the risk/benefit numbers for the specific case of the A380 cracks. I'm saying this analysis is grossly inadequate to justify grounding the A380, not that it shouldn't be grounded.)

The point you're missing is that it's a known problem that can be monitored for and affected planes can be serviced. If the causes weren't known I'd say at 10% they should be grounding the fleet and fixing the problem.

Yes there is a point where it gets to be too costly for the protection given, but that's generally when you don't know the cause and can't keep an eye on it. If they're spending that much to fix the problem then they're probably doing it wrong. In that case they ought to just monitor the problem and replace the particular parts needed rather than the entire fleet.

The things that really scare me are the flight crew and unknown problems.

Cars are only dangerous when you're bad at driving. Ever wondered why only a small fraction of drivers are involved in fatal or near-fatal car crashes each year? It's because the rest have above average driving skill. Ask them yourself if you don't believe me.

People who are actually good drivers (or flyers) know that there are some situations in which you are FUBAR. Like getting t-boned by someone running a red light, or like PSA Flight 182 [wikipedia.org] -- a 727 which collided with a Cessna 172 above San Diego, CA. Captain James McFeron's last words to the tower as the 727 descended in an uncontrolled plunge were, "This is it, baby", and that sums it up. Sometimes no matter how good you are, how much you prepare, you end up at the mercy of the universe's alternate plans for you.

Regarding the article, there's enough that can go wrong without having a plane come apart because some bean counter deemed it an acceptable risk.

That happened to my brother. The mechanic at the car dealer only put one nut on the wheel studs after replacing the brakes, and that one was on by only one turn. My brother was driving home in rush hour traffic when the wheel (left rear) came off, went bounding through the air, narrowly missed bouncing off two cars - one a cop car!, and fell off the road. My brother's truck came sliding to a sparking halt in the middle lane, blocking traffic for quite a while. No collisioins ensued, the cop never saw a thing. The car dealer repaired the truck of course - I think they had to replace the bed of the pickup.

Yep. Where most people get confused, is by conflating "value of MY life to ME" with "value of one citizen to society". They switch back and forth between these contexts in order to make whatever stupid "if it saves just one life" point they are working.

I think the best way to measure the value of a life to society is to look at per capita GDP.

For that matter, It is actually possible to determine the rational value people place on their lives. Of course you can't ask them directly, because you'll get gibberish... but you can ask it indirectly, by asking how much extra we'd have to pay them to take a job that has x% chance of fatality per annum.

The research has been done. They crunched the numbers and came out with $2-$10 million compensation for a job with 100% risk of fatality. The dollar amount somewhat depended on their current salary level. Interestingly, the dollar amount was pretty close to the average citizen's lifetime per capita GDP.

A new car built by my company leaves somewhere traveling at 60 mph. The rear differential locks up. The car crashes and burns with everyone trapped inside. Now, should we initiate a recall? Take the number of vehicles in the field, A, multiply by the probable rate of failure, B, multiply by the average out-of-court settlement, C. A times B times C equals X. If X is less than the cost of a recall, we don't do one.

Not killing people, but not going to extraordinary lengths to ensure no one dies either. There's a cost/benefit function. Should we pay people to patrol sidewalks 24/7 to make sure there's nothing slippery? This is the same thing. It's *very probably* not going to kill anyone, but it's not worth the time and money to "make sure" it won't, especially when there are no guarantees regardless.

Add to that the fact that no amount of prevention will prevent someone from *ever* dying, and it's just more wasted

Yes, the economy is more important than not killing people. In fact, can I kill you and take your money? It's for the good of society. That money's gotta keep changing hands. I'll be by tonite.

Ya'know, the article was really short:

Airbus recommends that airlines check for cracks but says they present no real danger. The BBC quotes the following from a statement by the company:

"We confirm that minor cracks were found on some noncritical wing rib-skin attachments on a limited number of A380 aircraft. We have traced the origin. Airbus has developed an inspection and repair procedure, which will be done during regular, routine scheduled four-year maintenance checks. In the meantime, Airbus emphasizes that the safe operation of the A380 fleet is not affected."

Isn't that mostly a function of peoples' monetary ability to pay for special treatments? I suppose this could make it slightly more expensive for the 875,000 americans who go to other countries to get cheaper treatments. Besides, don't the laws of supply and demand dictate ticket prices? Less demand = more money. I'm still trying to figure out, other than medical tourism, how a cheap plane ticket will extend my life.

The autopilot is not bugged. The autopilot wasn't even active for over four minutes before the crash. The headline is completely misleading, as the autopilot shut down as soon as conflicting airspeed readings came in. The system recognizes that it is unsafe to have a computer flying when the computer is getting faulty data. Thankfully Airbus flight computers are pretty good about error-checking, as they detected the airspeed discrepancy and acted on it - by turning control over to the crew and telling them why.

The accident appears to have been triggered by a number of events:

- Faulty pitot tubes providing faulty airspeed indications.- Weather radar that saw a little storm ahead, but not the big, fuck-off storm behind it until the pilots decided to fly through the small storm.- An avalanche of data coming into the cockpit during critical moments. During an emergency, it can be difficult to avoid focusing on a few bits of data, while others slip by.

The storm was recreated in an Airbus simulator for multiple flight crews. Using data the flight computer sent back to the maintenance crews during the flight, they were able to trigger the same errors (Pitot tube failure and airspeed mismatches).

1) the less experienced pilot was left on the stick while 1 pilot stayed there and the most experienced left for a pause.
2) once the indicator showed the wrong speed, the less experienced pilot started to climb up and regain altitude
3) this triggered stall warning to which the less experienced pilote answered by pulling the stick instead of pushing. THAT alone was the first terrible error. Most category of stall except rare one impossible with big airliner have you PUSH the stick to gain speed.
5) the

What Really Happened Aboard Air France 447 [popularmechanics.com] tells the story as it stands after investigations. It's a rather chilling read. But it makes one thing clear: it was about human error. The plane was even fully operational when it crashed, as an anti-icing system had managed to bring air speed sensors back to operation before it.

Two years after the Airbus 330 plunged into the Atlantic Ocean, Air France 447's flight-data recorders finally turned up. The revelations from the pilot transcript paint a surprising picture of chaos in the cockpit, and confusion between the pilots that led to the crash.

It'll be 'pilot error' - he should have checked over the world's largest plane for cracks that (obviously, not like these)- are not harmless.

Actually, it is the job of both the pilot and the lead ramp agent of the gate to do a walk around and check the airplane for visible signs of damage. In the case of the lead ramp agent, it must be done twice: both when the plane first taxis in and right before the plane takes off. And I believe the pilots of both crews (incoming crew and outgoing crew), if there is a crew change, do walk arounds as well. So, were a crack to form, unless it formed catastophically in flight (ie, breaks apart), there is a v

There's just not enough info in the article to argue the case either way. OTOH I doubt there's ever been an aircraft without minor design defects that are fixed as they appear.

All commercial airliners have a log book in the cabin with a list of known broken/defective bits that the pilots are supposed to read before every takeoff and where they write down any weirdness they notice during the flight. None of the books are empty, even on brand new aircraft (ask a pilot...)

I doubt there's ever been an aircraft without minor design defects that are fixed as they appear.

This is what happens when an airline is a launch customer (as are Qantas and Singapore I believe). When the airline is first in line to receive a new aircraft type, there are all kinds of bugs that the airline has to be willing to accept. For example, the first six production 787s [wikipedia.org] are overweight in comparison with what was promised. Similarly, I've heard time and time again not to buy the first model year of a new car or significant vehicle redesign because of potential problems that will be found only after production and then fixed in subsequent years.

Why? They're on record as saying that it's not critical. By which they almost certainly mean that monitoring it is sufficient. What independent 3rd party experts are you going to tap? Most of them work for either the competition or one of the regulatory bodies that's supposed to be keeping tabs on them.

Ultimately as others have pointed out, the amount of damage that this would do if one of those planes fell out of the sky because those cracks caused a wing to fall off would probably be the end of Airbus. Given that they're stress fractures on the wing it's quite likely that they were considered when designing the plane.

And if those parts are designed to experience some cracking, as part of some carefully tuned tradeoff? There was some high altitude spy plane (maybe the Blackbird?) that leaked fuel on the ground, because when operating the temperatures would cause things to expand, so it was better to have it leak on the ground than break in the air. If a layman, or even an engineer unfamiliar with the project, saw that, they would naturally assume something was wrong.

Actually, it isn't that it lost a lot of fuel before takeoff (although it did leak a bit), it's the fact that it couldn't takeoff at all with a full fuel load. The engines and airframe were optimized for high-speed, high-altitude flight. Lift and thrust characteristics were terrible in the low-altitude subsonic speed regime.

I'm no aircraft engineer, but I do not feel comfortable with all this "pose absolutely no danger"-talk. AFAIK, particularly modern aircraft are engineered to trim down on weight as much as possible, and I would be VERY surprised if there were parts in the plane that could just safely break down posing no risk whatsoever. Such parts wouldn't be there in the first place, now would they?

Why are we so strange behaving species? How about being more rational?

We are rational - we just suck at understanding the risk of thing sin everyday life.

To many false alarms or things that appear as false alarms, we ignore it. And most of the time it is the right thing to do. Because if we don't, we spend all of our time preparing for very unlikely or even improbably events.

Or another way we go over board is over estimating some risks while brushing aside others. Such as we have no problem jumping in a car and driving 70+ mph separated by just some dashed white lines but yet, we have to go through over zealous or even unnecessary security at airports.

Most likely we will die from a car accident, cancer, heart disease, gun shot, lightening strike and a few others things, but do we spend as much time and money on mitigating those risks let alone as much as we do on terrorism? Hardly.

Can I say yay to that idea? i'll gladly give up the right to drive myself if it means there won't be anymore morons with cell phones plowing right through lights because they were busy pushing buttons instead of steering that 2 tons of flying low death on wheels. I nearly lost my dad a couple of years back to a gal that ran a red light in an SUV and hit his 2 ton work van with enough force it rolled three times and it took the jaws of life to cut the driver's door off of him. I was real proud of him that da

Who's saying they are blowing it off?From what I understand, they are aware of the problem, have isolated it's cause, and deemed it non critical. And I do trust Airbus far enough that they do not want to see one of these planes fall out of the sky.

The cracks are for course troubling in such a young aircraft, but blowing issues out of proportion is about as bad as ignoring them.

Who's saying they are blowing it off?From what I understand, they are aware of the problem, have isolated it's cause, and deemed it non critical. And I do trust Airbus far enough that they do not want to see one of these planes fall out of the sky.

The cracks are for course troubling in such a young aircraft, but blowing issues out of proportion is about as bad as ignoring them.

Agree. The alternative is that the cracks really are critical but Airbus are playing down the problem because they've decided that having an accident, forcing them to ground the rest of the fleet anyway, having to pay out billions in damages and fines, and completely destroying their reputation, is a better option than grounding the fleet now and repairing the aircraft.

Before I listen to anyone's opinion that these cracks are more of a problem than Airbus say they are, i'd want to see some qualifications in metallurgy or similar discipline.

And some actual knowledge of the specific problem. Admittedly, I haven't done any metallurgy in 10 years, but I know enough to not trust anything the media say about very specific technical problems on a first attempt, metallurgy, computer science, physics, or anything.

Depends entirely on what is cracking and how much. It is routine for damage found on aircraft inspection to be reported to the manufacturer for engineering guidance.

Defect limits exist for many aircraft and engine components. For example, borescope (think "endoscope for machines") inspection of turbines is used to check allowable wear and damage. That can be considerable depending on the engine.

That's a non-sequitur if there ever was one. Yeah, small cracks have a tendency to become larger under stress. So what. They always did, and they always do, and any plane that's flying out there has plenty of small cracks. This tells us nothing. What we need to know is what is the predicted rate of growth of those particular cracks under the stresses the material at the crack tip, in particular, is subject to. Add in tasty details about expected contributions of structure (will the cracks join like in Tu-144?), corrosion, etc.

Take a close look at the skin of the jet next time you fly. You may be surprised how many metal patches you will find -- patches that repair cracks or dings/dents.

No, the Airbus FMSes go into alternate law when they lose speed data. In alternate law the FMS does not apply any envelope protections to control inputs - the pilots have unfettered control. This was the case in the AF447 crash. The reason for its crash appears to be that the 2nd co-pilot first stalled the aircraft at high altitude, and then continued to apply control-inputs that prevented the other pilot from recovering from the stall. AF447 was literally flown into the sea by the junior co-pilot. Sadly, b

I've seen some suggestion that if neither pilot presses the priority switch the inputs are algebraically summed. Do you know? I can not say that in all cases it would be better to have slaved yokes. I am aware of one fatal incident in a sailplane where the best guess is the passanger panicked and overpowered the pilot fighting for the stick. But I have to think it would be better to have some shared feedback between the sticks.

Depends on the aircraft. A Boeing 737 for instance has hydraulically boosted controls. There are steel cables from the flight deck controls to the ailerons and elevators (the rudder is purely hydraulic), so the B737 system is sort of like "power steering". With a complete hydraulic failure, you can still muscle a Boeing 737 around (although I suspect it will take both crew members hauling back on the controls at the same time to flare for landing). Some airliners of similar size to a B737 do not have hydrau

So are trains and cars (not to mention small planes, which are, mile for mile flown, much more dangerous than big planes). Everything has points of failure and is therefore unsafe in some way; the question can only be "how unsafe?"